Benzothiazole azo pyrazolone compounds



United States Patent BENZOTHIAZOLE AZO PYRAZOLONE COMPOUNDS James M. Straley, Kingsport, Tenn., and John Sagal, Jr.,

Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application August 20, 1954 Serial No. 451,282

13 Claims. (Cl. 260-147) This invention relates to new azo compounds and their application to the art of dyeing or coloring. More particularly it relates to certain metallized and non-metallized benzothiazole azo pyrazolone compounds and their application to the dyeing of various textile materials. Insofar as dyeing is concerned the invention is particularly directed to the dyeing of cellulose acetate textile materials with the metallized azo compounds of the invention.

The non-metallized monoazo compounds of our invention have the formula:

wherein Ar represents an ortho-arylene radical of the benzene series and Y represents the radical of a S-pyrazolone compound. The metallized azo compounds of our invention comprise the monoazo compounds having the Formula I in complex combination with chromium, cobalt, copper, iron, manganese, nickel and vanadium. The manner of preparing the non-metallized and metallized azo compounds of our invention is fully described hereinafter.

While our invention relates broadly to the non-metallized and the metallized monoazo compounds just described, the azo compounds of our invention are represented for the most part by the non-metallized and the metallized forms of the azo compounds having the formula:

wherein Ar represents an ortho-arylene radical of the benzene series, R represents a hydrogen atom, a phenyl radical, a methylphenyl radical, a chlorophenyl radical, a methoxyphenyl radical, an ethoxyphenyl radical, a nitrophenyl radical or a 2-benzothiazolyl radicals and R represents a methyl group, a carboxyl group, a carbomethoxy group, a carboethoxy group, an amino group, a hydroxy group or a trifluoromethyl group.

As is well known, one of the disadvantages dyed cellulose acetate textile fabrics suffer in comparison with some of the dyed competing textile fabrics, such as cotton, wool and viscose, for example, is lack of fastness to washing. Many schemes have been proposed to remedy this situation but all suffer from some significant fault. By means of our invention dyed cellulose acetate textile materials having good to excellent fastness to washing, light and gas are obtainable. These results may be obtained by dyeing the cellulose acetate textile material with the 2,832,761 Patented Apr. 29, 1958 that the invention is generally applicable to the dyeing of textile materials made of or containing a cellulose alkyl carboxylic acid ester having two to four carbon atoms in the acid groups thereof. By cellulose alkyl carboxylic acid esters having two to four carbon atoms in the acid groups thereof, we mean to include, for example, both hydrolyzed and unhydrolyzed cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate-propionate and cellulose acetate-butyrate. Celulose acetate has been particularly referred to because it is the most widely used cellulose alkyl carboxylic acid ester.

The non-metallized monoazo compounds of our invention are prepared by diazotizing a Z-aminobenzothiazole compound having the formula:

wherein Ar represents an ortho-arylene radical of the benzene series and coupling the diazonium compound obtained with a 5-pyrazolone compound. These compounds, in addition to being dyes for various materials identified herein, possess the important property of being metallizable. The metallized dyes formed therefrom have the valuable properties described herein.

The metallized monoazo compounds of our invention are prepared by treating the non-metallized azo compounds having the Formula I with salts of nickel, cobalt, copper, chromium, manganese, iron or vanadium. The non-metallized monoazo compounds can be metallized either on or off the fiber. Metallization can be carried out, for example, by treating the non-metallized dye with a solution or dispersion of the metallizing agent. though the metal complex is often formed at room tem perature, we prefer to accelerate the process by heating, usually with steam, for a short time. The preparation of the metallized monoazo compounds of our invention is fully described hereinafter.

Illustrative of the metallizing agents that can be employed are the halides, the sulfates, the acetates, the cyanides, and the thiocyanates of nickel, cobalt, chromium, manganese, iron and vanadium as'well as various copper compounds. Thus, nickel chloride, nickel bromide, nickel sulfate, nickel acetate, nickel cyanide, nickel formate, nickel thiocyanate [Ni(SCN) cobaltous bromide, cobaltic chloride, cobaltous chloride, cobaltous acetate, cobaltous cyanide, cobalt thiocyanate [Co(SCN) cupric chloride, cupric bromide, cupric acetate, cupric lactate, chromium trichloride, chromium tribromide, chromic sulfate, chromic acetate, chromium thiocyanate [Cr(SCN) manganese chloride, manganous sulfate, manganese acetate, manganese thiocyanate [Mn(SCN) ferric chloride, ferric 'fiuoride, ferrous acetate, ferrous thiocyanate [Fe(SCN) ferric thiocyanate Fe(SCN) and vanadium tribromide, are illustrative of the metallizing agents that can be employed.

When the metal complex is formed on a cellulose alkyl carboxylic acid ester, such as cellulose acetate fiber, the use of a metal thiocyanate appears to be advantageous and is preferred. Nickel thiocyanate appears to be especially useful and particular claim is laid to its use. Next to nickel thiocyanate the use of cobalt thiocyanate is preferred 2-amino-6-methylsulfonylbenzothiazole, 2 amino-6- ethylsulfonylbenzothiazole, 2-amino-6-n-propylsulfonylbenzothiazole, 2 amino-6-n-butylsulfonylbenzothiazole, 2-aminobenzothiazole-d-N-methylsulfonamirle, Z-arninobenzothiazole-6-N-ethylsulfonamide, 2 aminobenzothiazole-6-N-n-propylsulfonamide, 2-aminobenzothiazole-6- N-n-butylsnlfonamide, =2-amino-6-rnethoxybenzothiazole, 2-amino-.6-ethoxybenzothiazole, 2 amino-6-n-propoxy benzo thiazole, 2-amino-6-n-butoxybenzothiazole, Z-amino- 6-methylbenzothiazole, Z-amino 6 n propylbenzothiazole, 2-amino 6-n-butylbenzothiazole, 2 aminofl-hydroxyethylbenzothiazole, 2- amino-6-y hydroxypropylbenzothiazole, 2-amino-6-5-hydroxybutylbenzothiazole, 2-amino-6-acetylaminobenzothiazole, 2 amino 6-n-propionylaminobenzothiazole, 2- arnino-6-n-butyrylaminobenzothiazole, 2 amino-6-thi0- methylbenzothiazole, 2-amino-6-thiocyanobenzothiazole, 2-amino-6=cyanobenzothiazole, Z-amino-G-triflrioromethylbenzothiazole, Z-amino-o-chlorobenzothiazole, 2-amin0-6 nitrobenzothiazole, 2-amino l,7-dimethoxybenzothiazoie, 2-amino-5,-dirnethoxybenzothiazole; Z-arnino 4,7 diethoxybenzothiazole, and" 2-amino i,d dimethylbenzothiazole are representative of the Z-amiriobenzothiazolecompounds used in the preparation of the azo compounds of our invention.

3-methyl pyrazolone, 3 carboxy 5 pyrazolone,

3-carbomethoxy-5-pyrazolone; 3-carboethoxy-5-pyrazolone, 3-amino-5-pyrazolone, 3 hydroxy-5-pyrazolone, 3-

lone, l phenyl-3 -amino-5-pyra zolone,-"' l-phenyl3 hydroxy-S-pyrazolone, l-(2benzotbiazolyl)-3-amino-5-pyrazolone, 1-phenyl-3-methyl-5-p-nitrophenyl pyrazolone, 3-phenyl-5-pyrazolone, 1-phenyl-3-carbornethoxy-5-pyrazolone, 1-phenyl-3-carboethoxy-5-pyrazolone, 1,3-dimethyl- S-pyrazolone, 1-p-nitro-phenyl 3-methyl-5-pyrazolone, lo-nitrophenyl-3methyl-5-pyrazolone, l-p-methylphenyl- 3-methyl-5-pyrazolone, 1-p methoxyphenyl-3-amin0-5-pyrazolone, 1-p-methylphenyl-3-amino-5-pyrazolone, l-ochlorophenyl-S-amino-5-pyrazolone, l-p chlbrophenyl-S- amino-S-pyrazolohe, 1-p-ethylphenyl-S-inethyl-S-pyrazolone, l-p-chlorophenyl-3-methyl-S-pyraZoione, l-(2-benzothiazolyl) 3-methyl-5-pyrazolone and l-(2-benzothiazolyl)-3-carbomethoxy-5-pyrazolone, for example, are illustrative of the pyrazolone compounds used in the'preparation of the azo compounds'of our invention.

The'non-metallized monoazoidye compounds of our invention have varying utility for the dyeing of cellulose alkyl 'carboxylic acid esters having .two to four carbon atoms ,in the acid groups thereof, nylon, acrylonitrile polymers, such a polyacrylonitrile and acrylom'trile graft polymers, and polyesters, such as polyethylene tere'phthalate. v After application to these materials, usually in the form of textile materials, the dye may be nietallized thereon, if desired. The metallized azo compounds of our inventioncan be applied by ordinary dyeing or printing techniques to nitrogenous textile materials such as wool, silk, nylon and acrylonitrilje polymers, for example. Coloratiori can also be eif'ec ted by incorporating the nonrnetallized or met'ailized azo compounds intotlie spinning dope, spinning the fiber as usual and converting the nonmetallized azo compounds to'their metallized form if desired. Also the metallizing agent can be incorporated in the spinning dope, the fiber spun as usual and then dyed with the non-inetallized monoazo compounds to form the metalcomplex on the fiber. The newmetallized dyes of our invention are preferably formed by heating the non-metallized azo dye with the metallizing agent in organic solvents, such as, for example, cellulose; acetate, cellulose acetate propionate, acrylonitrile poi ymers, polymides, ethylene glycol monomethyl ether and formamide.

Both the non-metallized and metallized rncnoazo compounds of our invention are dyes for fibers prepared from 2 amino-6-ethylbenzothiazole,

formed polymer can be a homopolymer (a polymer prepared by polymerization of a single monomer) or it can be an interpolymer such as a copolymer (a polymer prepared by the simultaneous polymerization in a single reaction mixture of two monomers) or a terpolymer (a polymer prepared by the simultaneous polymerization in a single reaction mixture of three monomers), or the like, and the graft polymers for which the dye are particuiarly useful are those containing at least 5% by weight of combined acrylonitrile grafted to the preformed polymer molecule. i

T he graft polymers which can be dyed using the nonmetailizcd and metalliz ed dyes are thus polymers having directed placement of the polymerized monomeric units in the graft polymerv molecule as distinguished from the random distribution obtained in interpolymers which are prepared by simultaneous polymerization of all of the monomeric "materials. in the polymer. The preformed polymer can be either a homopolymer of any of the well-knownpolymerizable monomers containing a single CH=.C group and .desirably a CH C group, or an inte'rpolymer oftwo or more of such monomers; and the grafting can be clfected with the preformed homopolymer or interpolymer in the polymerization mixtrifluoromethyl-S-pyrazolone, 1-phenyl-3-me thyl-S-pyrazoture in which it was formed (i. e. a live polymer) or with the preformed polymer isolated from the polymerization mixture in which it was" formed (i. e. a dead polymer).

The preformed polymer desirably is a homopolymer of a vinyl pyridine, an acrylamide, a maleamide, a fumaramide, an acrylatepa methacrylamide, a methacrylate, an itaconamide, acitraconarnide, a fumaramate, an itaconamate, a citraconar'nate, a maleamate, or a. vinyl ester; or an interpolymer. of two or, moreof such monomers with each other or of at, least one. of such monomers with one or more diiferent monoethylcnic monomers characterized by a -CH=C group such as .styrene, acrylonitrile, substituted styrenes, vinyl or vinylidene chlorides, vinyl ethers, dialkyl malcates, alkenyl ketones', dialkyl fumarates, acrylic acid, methacrylieacid, substituted acrylonitriles, fumaronitrile, ethylene and the like.

The graft polymerization is effected by polymerizing acrylonitrile or. a mixture of acrylonitrile with any other monoethylenic monomer, including any of the monomers enumerated hereinabove, with the preformed live or dead homopolymcr or interpolymer whereby the acrylonitrile alone or together with another grafting monomer is combined with the preformed polymer molecule to give a graft polymer containing from 5 to by weight of combined acrylonitrile.

The new azo compounds of our invention are of particular utility for dyeing fibers prepared from a graft polymer obtained by graft polymerizing acrylonitrile and an acrylamide or methacrylamide with a preformed copolymer of acrylonitrile and the same or different acrylamide or methacrylamide.

U. S. Patent 2,620,324, issued December2, 1952; U. S. Patent 2,649,434, issued August 18, 1953; and U. S. Patent 2,657,191, issued October 27, 1953, disclose other typical graft polymers that can be dyed with the new azo compounds of our invention.

The following examples in which parts are expressed by weight illustrate our invention.

EXAMPLE 1 i 61 parts of concentrated sulfuric acid (94%) were added 'to a slurry of 5.7 partsof 2-amino-6-methylsulfonylbenzothiazole in 60 parts of water. An exothermic reaction was observed as the amine passed into solution. The resulting solution was cooled to 10 C. and a solution prepared bydissolving 2.1 parts of sodium nitrite in 24 parts of concentrated sulfuric acid was added while maintaining the temperature of the reaction mixture below 5 C. After complete addition of the sodium nitrite, the reaction mixture was stirred for 2 hours at about C. The diazonir in solution of 2-amino-6- methylsulfonylbenzothiazole thus formed was added, with stirring, to a solution of 4 parts of 3-carboethoxy-5- pyrazolone in 75 parts of propionic-acetic (1:5) acids at 0 C. The reaction mixture was then stirred for 1 hour at 5 C. and the mineral acid was made neutral to Congo red paper by the addition of ammonium acetate. The reaction mixture was then drowned in 1000 parts of water and the dye compound which precipitated was recovered by filtration, washed with water until neutral and dried under vacuum at about 50 C. 6 to 8 parts of a dye compound having the formula:

were obtained. It dyes cellulose acetate yellow shades.

EXAMPLE 2 A solution of 3.8 parts of sodium nitrite in 45 parts of concentrated sulfuric acid was added, with stirring, to a solution of 9.1 parts of 2-amino-6-methoxybenzothiazole in 50 parts of propionic-acetic (1:5) acids. 50 parts of propionic-acetic (1 :5) acids were then added with stirring and stirring was continued at 0 C. for 2 hours. The diazonium solution resulting was then added at 0 C. to a solution of 11.6 parts of 1-(2-benzothiazolyl)-3-amino- S-pyrazolone in 150 parts of propionic-acetic (1:5) acids. The mineral acid present in the reaction mixture was made neutral to Congo red paper by the addition of ammonium acetate. The reaction mixture was then drowned in 1500 parts of cold water and the dye compound which precipitated was recovered by filtration, washed with cold water until neutral and dried under vacuum at about 60 C. Sodium acetate can be used in place of ammonium acetate to neutralize the mineral acid if desired. The dye compound obtained dyes cellulose acetate yellow shades.

EXAMPLE 3 A solution of 3.8 parts of sodium nitrite in 45 parts of concentrated sulfuric acid was added, with stirring, at -5 C. to a solution of 11.8 parts of 2-amino-6-methylsulfonylbenzothiazole in 200 parts of 60% sulfuric acid. The reaction mixture thus obtained was stirred for 1 hour at about 0 C. and then added to a solution of 8.7 parts of 1-pheny1-3-methyl-5-pyrazolone in 160 parts of propionic-acetic (1:5) acids at 0 C. The reaction mixture was then made neutral to Congo red paper by the addition of ammonium acetate, stirred for 2 hours and then drowned in 1600 parts of cold water. The dye compound which precipitated was recovered by filtration, washed with cold water until neutral and dried at 60 C. 15.5 parts of a dye compound which dyes cellulose acetate and nylon yellow shades were obtained.

EXAMPLE 4 A solution of nitrosyl sulfuric acid was prepared by dissolving 3.8 parts of sodium nitrite in 45 parts of concentrated sulfuric acid. After cooling the nitrosyl sulfuric acid mixture to 10 C., 50 parts of propionic-acetic (1 :5) acids were added and the temperature of the resulting mixture was brought to 5 C. or lower after which 9.1 parts of 2-amino-6-methoxybenzothiazole in 50 parts of propionic-acetic (1:5) acids were added with stirring in about minutes time below 5 C. After addition of the 2-amino-6-methoxybenzothiazole, the reaction mixture was held for 2 hours at 5 C. and then stirred into a solution of 8.3 parts of l-phenyl-3-amino-5-pyrazolone in 150 parts of propionic-acetic (1:5 acids at 5 C. The

,6 coupling reaction which takes place was completed by neutralizing the reaction mixture to Congo red paper with ammonium acetate following which it was stirred for 2 hours at room temperature. Following this the reaction mixture was drowned in 1000 parts of cold water and the dye product which precipitated was recovered by filtration, washed well with cold water and dried under vacuum at 50 C. 17.2 parts of a dye compound which dyes cellulose acetate bright yellow shades were obtained.

EXAMPLE 5 Cellulose acetate tricot dyed with a 3% dyeing of the dye product of Example 3 was padded with a 2% aqueous solution of nickel thiocyanate under conditions such that a 60 to takeup, based on the weight of the goods, was obtained. The cellulose acetate tricot was dried and then aged in a steam chest at 5 p. s. i. pressure. The cellulose acetate goods were then scoured at 80 C. with soap and water, rinsed well with water and dried. The cellulose acetate tricot was dyed a beautiful golden yellow shade. No bleeding was observed when a sample was subjected to an AATCC wash test at 160 F. using sodium carbonate. Further, While the original dyeing showed a break after only 4 hours on the Fade-Ometer, the metallized dyeing showed no break whatsoever after 20 hours on the Fade-Ometer.

EXAMPLE 6 Example 5 was repeated using a 2% aqueous solution of cobalt thiocyanate instead of nickel thiocyanate. A greener and somewhat duller shade of yellow of equal lightand wash-fastness properties was obtained.

EXAMPLE 7 A cellulose acetate fabric dyed to a depth of 3% with the dye product of Example 3 was padded with a solution of 6 parts of Cuprofix (a mixture of copper sulfate and a low urea-formaldehyde polymer) in 200 parts of water, and then dried at C. The padded cellulose acetate fabric was then cured at 160 C. for 5 minutes and then scoured at 60 C. with a solution of 1 part of Calgon (sodium hexa-meta-phosphate) and 1 part of Igepal CA (a polymerized ethylene oxide-alkyl phenol condensation product) in 1000 parts of water, rinsed and dried. The cellulose acetate fabric was colored a golden yellow shade having excellent fastness to the action of laundering agents.

EXAMPLE 8 A 3% dyeing with the dye product of Example 3 was made on a cellulose acetate yarn containing 1% of chromium trichloride. The yarn was then steamed at 10 pounds pressure for 30 to 40 minutes following which it was scoured at 80 C. with soap and water and dried. By this treatment the cellulose acetate yarn is dyed a rich golden brown shade which has excellent wash fastness.

EXAMPLE 9 1 part of the dye of Example 4, 0.5 parts of ammonium carbonate and 1 part of nickel acetate in 50 parts of forrnamide were heated together at C.- C. for 10 hours. Following this the reaction mixture was cooled to room temperature and drowned in 500 parts of water. The dye compound which precipitated was recovered by filtration, washed well with Water and dried at 100 C. 1.2 parts of a dye compound which colors nylon, silk, wool and polyacrylonitrile modified with 10% of 2- methyl-5-viny1 pyridine orange shades were obtained.

EXAMPLE 10 A solution of nitrosyl sulfuric acid was prepared by dissolving 3.8 parts of sodium nitrite in 45 parts of concentrated sulfuric acid. After cooling the nitrosyl sulfuric acid mixture to 10 C., 50 parts of propionicacetic (1:5 acids were added and the temperature of the resulting mixture was brought to 5 C. or lower after was stirred for 2 hours at room temperature. ing this the reaction mixture was drowned in 1000 parts which 9.8 parts of Z-amino-G-ethoxybenzothiazole in 50 parts of propionic-acetic (1:5) acids were added with stirring in about 15 minutes time below 5 C. After addition of the Z-amino-6-ethoxybenzothiazole, the reaction mixture was held for 2 hours at 5 C. and then stirred into a solution of 8.3 parts of 1-phenyl-3-amino- S-pyrazolone in 150 parts of propionic-acetic (1:5) acids at 5 C. The coupling reaction which takes place was completed by neutralizing the reaction mixture to Congo red paper with ammonium acetate following which it Followof cold water and the dye product which precipitated was recovered by filtration, washed well with cold water and dried under vacuum at 50 C. 17 parts of a dye compound which colors cellulose acetate yellow shades were obtained It colors the acrylonitrile graft polymer specifically described hereinafter somewhat redder shades of yellow having good light-fastness properties.

EXAMPLE 11 A solution of nitrosyl sulfuric acid was prepared by dissolving 3.8 parts of sodium nitrite in 45 parts of concentrated sulfuric acid. After cooling the nitrosyl sulfuric acid mixture to C., 50 parts of propionicacetic (1:5) acids were added and the temperature of the resulting mixture was brought to 5 C. or lower after which 7.6 parts of 21aminobenzothiazole in 50 parts of propionic-ac'etic (1:5) acids were added with stirring in about minutes time below 5C. After addition of the Z amintSbenZOthiaZoIe, the reaction mixture was held for 2 hours at 5 C." and then stirred into a solution of 8.3 parts of l-phenyl-3-amino-S-pyrazolone in 150 parts of propionic-acetic (1:5) acids at 5 C. The coupling reaction which takes place was completed by neutralizing the reaction mixture to Congo red paper with ammonium acetate following which it was stirred for 2 hours at room temperature. Following this the reaction mixture was drowned in 1000 parts of cold water and the dye product which precipitated was recovered by filtration, washed well with" cold water and dried under vacuum at 50 C. The dye compound obtained colors cellulose acetate, nylon, wooland the polyacrylonitrile graft polymer specifically described hereinafter bright yellow shades which have good-fastness to light.

EXAMPLE 12 By the use of 7.5Tparts of 3-phenyl-5-pyrazolone in Example 4 in place of 11phenyl-3-arnino-5-pyrazolone a dye compoundjs obtained which colors the polyacrylonitrile graft; polymer specifically described hereinafter orange shades having good fastness to light. When Example 5. was repeated using a 3% dyeing on cellulose acetate tricot with the produc't of this example, the cellulose acetate fabric was dyed a bright orange shade having good fastness to light and washing.

EXAMPLE 13 g I (HOCHZCHZOCHQ).

6.8 parts of nickel acetate (Ni[OOCCH .4H O) and 2.8 parts of sodium carbonate were refluxed together with stirring for 8 hours. After cooling, the reaction mixture was drowned in 4000 parts of water and the dye compound which precipitated was recovered by liltration, washed well with cold water and dried. 12.2 parts of a dye compound containing 6.03% of nickel were obtained as a light brown powder. The dye product of this example when dispersed by grinding in cellulose acetate dope and extruded in the usual fashion, produced golden yellow yarn of excellent resistance to the action of light and wet processing.

iii

and dried at 60 C.

. 8 EXAMPLE 14 (HOCH CH OCH 6.8 parts of nickel acetate (Ni[OOCCH .4l-I O) and 2.8 parts of sodium carbonate were refluxed together with stirring for 8 hours. After cooling, the reaction mixture was drowned in 4000 parts of water and the dye compound which precipitated was recovered by filtration and washed well with cold water. The wet dye cake thus obtained was suspended in600 parts of water and 10 parts of ethylene glycol were added and the resulting mixture was brought to C. with good agitation (an equivalent amount of glycerine, ethylene glycol monomethyl ether or-other wetting agents can be used in place of the ethylene glycol). At this point 50 parts of a 16% nickel thiocyanate solution were added and the reaction mixture was held at 95 C. to C. for 10 hours. The reaction mixture was cooled and the dye pigment which had precipitated as recovered by filtration, washed well with water and dried. 16.6 parts of a metallized dye compound which imparts beautiful orange shades when properly incorporated .into plastic materials were .obtained.

EXAMPLE 15 The dye product of Example 10 was treatedjin accordance with the procedure described in Example '14. The metallized dye compound obtained similarly imparts orange shades when properly incorporated into plastic materials. r

EXAMPLE 16 Example 4 was repeated using 10.5 parts of 2-amino- 4,7-dimethoxybenzothiazole in place of 2-amino-6-methoxybenzothiazole. 17.1 parts of a dye compound which colors the polyacrylonit-rile graft polymer specifically dcsciibed hereinafter golden yellow shades were obtained. When 10 parts of this dye compound was metallized exactly in accordance with the procedure described in Example 13, a metallized dye compound which imparts fast yellow shades when properly incorporated into plastic materials was obtained.

EXAMPLE 17 t 9.1 parts of 2-amino-4-methoxybenzothiazole were diazotized in accordance with the procedure described in Example 4 and the diazonium compound obtained was added to a solution of 8.7 parts of l-phenyl-3-methyl-5- pyrazolone in parts of propionic-acetic (1:5) acids at 0 C. Upon completion of the coupling reaction, the reaction mixture was made neutral to Congo red paper with ammonium acetate and after 2 hours further stirring, the reaction mixture was drowned in 1600 parts of cold water. The dye compound which precipitated was recovered by filtration, washed until neutral with water 14.5 parts of a dye compound which colors nylon, .and the polyacrylonitrile graft polymer specifically described hereinafter orange shades were obtained. The nickel complex of this dye compound was prepared following the procedure described in Example 14.

The following tabulation further illustrates the monoazo compounds of our invention and sets forth the colors the non-metalliized compounds yield on cellulose acetate, an acrylonitrile' graft polymer and nylon, as well as the colors obtained on cellulose acetate when the non-metallized compounds are metallized on the fiber. The preparation of the acrylonitrile graft polymer referred to in the tabulation is described immediately following'the tabulation- C. A. refers to cellulose acetate, Original refers to the metallized dye compounds.

Color on O. A. Color on 2-Am1nobenzothlazole Metallizing Acrylonitnle Compound Coupling Component Agent Graft Polymer and Nylon Original Final Original 6-Methylsu1tony1. l-Phenyl-Zi-methyl-S-pyrazolone Ni(S N)ay w-.. yellow Do a do o orange.

Do ye ow B Do.

6.0 Do 0 Do.

yano

Do Do. 6-Ni1t)ro u d DO.

0 o 113g 1-P11551 1-3-rnethyl-5-pyrazo1one g f }red-orange, 4.1%i i iiill i riieziyi -hifihH-t byiidibfiI" ellow Wm DoIIII: 7 yellow U} DO D 6-6-Hyr1roxyethyL Do d brown. Do do Fe(SON)a. do black fi-Meighoxyu 1-Phenyl-3-methyl-5-pyrazolone. )2--- Y g o a o Dom. 3-Trifluoromethy1-5-pyrazo1one Do. do

3-Carboxy-5-pyrazolone o 1-p-Nitrophenyl-3-methyl-5-pyrazolon D0. D0.- do

l-Phenyl-Ii-arnino-5-pyrazolone D0. Do. D0. Do. Do. Do. C0(SCN)2 Ni(SON)2 D0 1 2 do Go(SON)z.. 3-l\I%thyl-5-pyrazolone ggs gllggz... D0 O L 2..

l-Phenvl-li-meth l-5-o razolone. )2.. do K wi 3-M th 1-5- 1 w -10Z i f? i. 9 11 3)?" i 3-Ph 1 01 n 1 2..- ti iifi i f fif 0 s0N 1. 1-(2,%,6-Trichlorophenyl)-3-phenyl-5-pyra- )2..- 0ran Do .ffa fil 1 0 1- -1 1 1-3- t1 1-5- a lone. 1 2... Y Do-. t i dg f il f ?y 2 Co(SCNlz o fi-EthOXY l-(2,4,6-Trichlorophenyl)-3-rnethyl-5-pyra- )2 zolone. red-orange. $5580? 1 z 0 gr ggg) }oran e ea er 1 v 00(SON). d

Preparation of acrylonitrile graft polymer 3.0 g. of acrylonitrile and 7.0 g. of N-rnethyl methacrylamide were emulsified in 40 cc. of water containing 0.15 g. of potassium persulfate and 0.01 g. of tertiary dodecyl mercaptan. The emulsion was heated at C. until 94% or more of the monomers had copolymerized. This result is usually accomplished by heating for about 12 hours. The copolymer contained approximately 30% by weight of acrylonitrile and 70% by weight of N- methyl methacrylamide. The mixture was then cooled to room temperature, 50 cc. of water added and the mixture agitated until a homogeneous solution of dope containing 10% by weight of the copolymer resulted.

30.7 g. (3.07 g. of copolymer) of the above prepared solution or dope of the copolymer were placed in a changer. There were then added 10 g. of acrylonitrile, 114 cc. of water, 0.58 g. of phosphoric acid, 0.1 g. of potassium persulfate, 0.17 g. of potassium metabisulfite, 0.1 g. of tertiary dodecyl mercaptan and 0.56 g. of a 30% solution in water of N-methyl methacrylamide and the mixture heated, with stirring, to 35 C. and then allowed to level off at 37-39 C. After the heat of polymerization had been removed and when the conversion of the acrylonitrile to polymer had reached 96% or more, which is usually accomplished in a period of about 12 hours, the temperature was raised to C. The mother liquor was removed by centrifuging the polymerization mixture, the polymer precipitate being reslurried twice with water and centrifuged to a 70% moisture cake. The cake was dried under vacuum at 80 C. in an agitated dryer. The overall yield of modified polyjacketed reactor provided with an agitator and heat ex- 75 acrylonitrile product was over 90%. After hammerstored in a moisture proof container.- 3

uct in N,N-dimethylformamide into a precipitating batlnjhad a softening temperature of about 240 'C., an extensibility of about 20-30percent dependingon the draft ing and relaxing conditions, and showed excellent affinity for dyes.

soluble in N,N-dimethylformamide.

In order that the preparation of the azo compounds of I 7 our invention may be entirely clear, the preparation of.

certain intermediates used in their manufacture is de-;

scribed hereinafter.

Preparation of 2-amin0-6-methylsulfonylbenzothiazole A solution of 200 parts of bromine in300 parts of V acetic acid was added over the course of about 1 hour to a mixture of 1 71 parts of p-aminophenylmethylsulr tone and 202 parts of sodium thiocyanate 'in' 1750 parts,

added until 'the pH of the reaction mixture was about 6. The reaction mixture was then cooled, filtered and the reaction product which collected on the filter was washed well with water and dried at 120 C. 160 parts of Z-amino-6-methylsulfonylbenzothiazole were obtained as light yellow crystals melting at 226 C.-22 8 C.

Preparation 1 of 2-acetylamino-6-thiocyanobenzothiazole To a solution of 18.6 parts of aniline and 30.4 parts of ammonium thiocyanate in 300 parts of acetic acid at C., 14.2 parts of chlorine were bubbled in at 15 C.-

17 C. minutes after additionof the chlorine 15.6,

parts of sodium acetate and 30.4parts of ammonium thiocyanate were added to the reaction mixture. While holding the temperature of the reaction mixture below 7 35 C., 14.2 parts of chlorine were passed in and the reaction mixture was stirred overnight at room tempera ture. The solid present in the reaction mixture was recovered by filtration, washed with parts of acetic acid and then suspended in 600 parts of Water. The mixture thus obtained was heated to boiling and filtered. 30 parts of sodium acetate were added to the filtrate and the solid which precipitated was collected at 70 C. on

a filter, washed with 200 parts of cold water and dried at 100 C. 30 parts of a product melting at 187 C.-188 C. were thus obtained.

30 parts of acetic anhydride were added at 80 C. to a solution of 52.6parts of the above'product in 81 parts of acetic acid, and the temperature of the reaction mixture was held at 80 C.90 C. for one hour. The reaction mixture was then poured into 1000 parts of cold water and the product which precipitated was recovered by filtration, washed with 500 parts of water and then dried at 60 C. 62 parts of Z-acetylamino-G-thiocyanobenzothiazole melting at 247 C.-249 C. were thus obtained.

Preparation of Z-amin0-6-ethylsulfonylbenzothiazole A solution of 26.4 parts of crystalline sodium sulfide and 24.9 parts of 2-acetylamino-6-thiocyanobenzothiazole in 150 parts'of ethyl alcohol were refluxed together for 10 minutes and after cooling the reaction mixture to 20 C.,' 16.3 parts of ethyl iodide were added at one time and the reaction mixture resulting was refluxed for 12 one hour. The reaction mixture was then poured into 1000 parts of water and the product which precipitated was recovered by filtration, washed well with water and dried at 60 C. 23.6 parts of 2-acetylamino-6-ethylthiobenzothiazole melting at 168 C.-169 C. were obtained. If desired, the quality of the product can be checked by hydrolyzing a little of the product with acid to 2-amino-6-ethylthiobenzothiazole melting at 137 C.-

l9 parts of 30% aqueous hydrogen peroxide were added to a solution of 15.5 parts of 2-acetylamino-6- ethylthiobenzothiazole in 53 parts of acetic acid while maintaining the temperature of the reaction mixture between C.- C. The reaction mixture was maintained at this temperature for one. hour and then poured into 500 parts of cold water. The' solid present in the reaction mixture was recovered by filtration and then suspended in a mixture of 800 parts of water and parts of concentrated hydrochloric acid. The reaction mixture thus obtained was heated to boiling and then filtered. The filtrate was neutralized with sodium acetate, cooled to 25 C. and filtered. The product collected on the filter was washed with cold water and dried at 60 C. 8.5 parts of 2-arnino-6-ethylsulfonylbenzothiazole melting at 173 C.-175 C. were thus obtained.

Preparation of Z-amino-6-isopr0pylsulfonflbenzothiazole This compound was prepared in accordance with the procedure described for the preparation of 2-amino-6- ethylsulfonylbenzothiazole using 1 7.76 parts of isopropyl iodide in place of ethyl iodide. The melting point of the Z-acetylamino-6-isopropylthiobenzothiazole formed during the process was 174 C.175 C. while that of the final product Z-amino-6-isopropylsulfonylbenzothiazole was 207 C.-209 C.

2-arnino-6-n-propylsulfonylbenzothiazole is similarly prepared by the use of 17.76 parts of n-propyl iodide in place of isopropyl iodide in the foregoing example.

Preparation of Z-amino-d-isobutylsulfonylbenzothiazole This compound was prepared in accordance with the procedure described for the preparation of 2-arnino-6- ethylsulfonylbenzothiazole using 14.3 parts of isobutyl bromide in place of ethyl iodide. The melting point of the Z-acetylamino-6-isobutylthiobenzothiazole obtained was 167 C.-168 C. while that of the final product 2- amino-6isobutylsulfonylbenzothiazole was 206 C.- 207 C.

2-amino-G-n-butylsulfonylbenzothiazole is similarly prepared by using 14.3 parts of n-butyl bromide in place of isobutyl bromide in the foregoing example.

Preparation of Z-amino-d-trifluoromethyLrulfonylbenzothiazole 75 parts of bromine in 120 parts of acetic acid were added gradually with stirring to a solution of 98 parts of p-aminophenyltrifiuoromethylsulfone and .76 parts of sodium thiocyanate in 700 parts of'acetic acid. The additionof the bromine was begun at room temperature and the temperature of the reaction mixture was kept below 35 C. during the addition. The temperature ordinarily rises to about 32 C. The reaction mixture resulting was stirred for 24 hours at room temperature following which it was poured into 5000 parts of cold water and the mineral acid therein neutralized by the addition of sodium acetate with good stirring. The product which formed was recovered by filtration, washedwell with .cold water and dried at C. 33. to 70 parts of 2-amino-6-trifluorornethylsulfonylbenzothiazole melting at 206-208 C. were thus obtained.

' added dropwise, with stirring, to a solution of 12.4parts of p-aminobenzotrifluoride and 12.7 parts of sodium thiocyanate in 115 parts of acetic acid while maintaining the temperature of the reaction mixture below 35 C. The reaction mixture resulting w:-.s stirred for 12 hours following which the solid present therein was removed by filtration. The filtrate was poured into 1000 parts of water and the mineral acid therein was neutralized by the addition of sodium acetate with good agitation. The product which formed was recovered by filtration, washed well with cold water and dried under vacuum at 45 C. 7.7-10.2 parts of 2-amino-G-trifiuoromethylbenzothiazole melting at l15.5ll6.5 C. were thus obtained.

Another alkali metal thiocyanate such as potassium thiocyanate, for example, can be used in place of sodium thiocyanate in the last two of the foregoing examples. Similarly, another alkaline agent, such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium acetate or potassium ace tate, for example, can be used to neutralize the mineral acid in place of sodium acetate.

The preparation of p-aminophenyltrifluoromethylsulfame is described in British Patent 485,592.

The non-metallized monoazo dye compounds of our invention can be applied to cellulose alkyl carboxylic acid esters having 2 to 4 carbon atoms in the acid groups thereof, nylon, an acrylonitrile polymer, such as polyacrylonitrile and acrylonitrile graft polymers, and polyester, such as polyethylene terephthalate, textile materials and the metallized azo dye compounds of our invention can be applied to nitrogenous textile materials such as, for example, wool, silk, nylon and acrylonitrile polymers, such as polyacrylonitrile and acrylonitrile graft polymers, in the form of an aqueous dispersion and are ordinarily so ap plied.

To illustrate, the dye compound is finely ground with a dispersing agent such as sodium lignin sulfonate, Turkey red oil, soak, or an oleyl glyceryl sulfate and the resulting mixture is dispersed in Water. The dye bath thus prepared is heated to a temperature approximating 45 C.- 55 C. and the textile material to be dyed is immersed in the dyebath, following which the temperature is gradually raised to 80 C-90 C. and maintained at this temperature until dyeing is complete, usually one-half to two hours. From time to time throughout the dyeing opera tion, the material is worked to promote even dyeing. Upon completion of the dyeing operation, the textile material is removed from the dye bath, washed with an aqueous soap solution, rinsed well with water and dried. In the case of certain of the acrylonitrile graft polymers described hereinbefore it is necessary to dye at the boil for an extended period of time. Instances may be encountered where the fiber is not satisfactorily colored by the dyeing procedure just described. In these instances special dyeing techniques, such as the use of pressure, for example, developed by the art for the coloration of materials difficult to color may be employed.

Widely varying amounts of dye can be used in the dyeing operation. The amount of dye used can be, for example, /3 to 3% (by weight) of that of the textile material although lesser or greater amounts of the dye can be employed.

The following example illustrates one satisfactory way in which the fibers of the acrylonitrile graft polymers can be dyed using either the non-metallized or metallized azo compounds of our invention. 16 milligrams of dye are ground with an aqueous solution of sodium lignin sulfonate until well dispersed or alternately the dye can be dissolved in 5 cc. of hot ethylene glycol monoethyl ether. The dispersion or solution, as the case may be, is then poured into 150 cc. of water to which a small amount of a surface-active agent such as Igepon T Nekal BX (sodium alkylnaphthalenesulfonate) or Orvus (sodium lauryl sulfate-type) has been added. The dye bath is then brought to the desired temperature and 5 grams of well wet-out fibers of the graft polymer are added thereto. Dyeing is continued until the proper shade is reached. From ti is to time throughout the dyeing operation, the material is worked to promote even dyeing.

The expression propionic-acetic (1:5) acids refers to a mixture of propionic and acetic acids in which there are five parts by volume of acetic acid to 1 part by volume of propionic acid.

The non-metallized azo compounds dye nylon substantially the same shade as they dye acrylonitrile polymers.

Acrylonitrile graft polymers including those of the type specifically described hereinbefore are described and claimed inCoover U. S. application Serial No. 408,012, filed February 3, 1954. 2-amino-6-trifluoromethylsulfonylbenzothiazole is described and claimed by. Straley and Fisher U. S. application Serial No. 413,954, filed March 3, 1954 (now abandoned). 2-amino-6-trifiuoromethylbenzothiazole is described and claimed by Straley and Fisher U. S. application Serial No. 413,955, filed March 3, 1954 (now abandoned). v

We claim:

1. As a composition of matter, the azo compounds selected from the group consisting of monoazo compounds and their metal complexes containing a metal selected from the group consisting of chromium, cobalt, copper, iron, manganese, nickel and vanadium, said monoazo compounds having the formula:

wherein Ar represents an ortho-arylene radical of the benzene series devoid of a sulfonic acid group and Y represents the radical of a S-pyrazolone compound.

2. A complex metal compound which contains one of the metals selected from the group consisting of chro mium, cobalt, copper, iron, manganese, nickel and vanadium in complex combination with a monoazo compound having the formula:

wherein Ar represents an ortho-arylene radical of the benzene series devoid of a sulfonic acid group, R represents a member selected from the group consisting of a hydrogen atom, a phenyl radical, a methylphenyl radical, a chlorophenyl radical, a methoxyphenyl radical, an ethoxyphenyl radical, a nitrophenyl radical and a 2- benzothiazolyl radical and R represents a member selected from the group consisting of a methyl group, a carboxyl group, a carbomethoxy group, a carboethoxy group, an amino group, a hydroxy group and a *trifluoromethyl group.

4. Complex nickel compounds of the monoazo compounds having the formula set forth in claim 3.

5. Complex cobalt compounds of the monoazo compounds having the formula set forth in claim 3.

6. Process for the manufacture of azo compounds con- 11. A *complex' nickel compound of the azo comtaining nickel in complex union which comprises reacting pound having the formula: a monoazo compound having the formula set forth in a c s I claim 2 with nickel thiocyanate. 1

7. vProcess for the manufacture of azo compounds con- 5 c-N=N-c-CO taining nickel in complex union which comprises reacting l it a monoazo compound having the formula set forth in Y N claim 3 with nickel thiocyanate.

8. The monoazo compounds having the formula: H

12. The aZo compound having the formula:

C N=N Y onsets H f N v t C -N=N--CGHs wherein Ar represents an ortho-arylene radical of the hem I 6 it zene series devoid of a sulfonic acid group and Y represents the radical of a S-pyrazolone compound.

9. The monoazo compounds having the formula:

O: 13. The azo compound having the formula:

, r S r p p R omo wherein Ar represents an ortho-arylene radical of the ben- CN=N-C:J--CC zene series devoid of a sulfonic acid group, R represents 21' member selected from the group consisting of a hydrogen atom, a phenyl radical, a methylphenyl radical, a H chlorophenyl radical, a methoxyphenyl radical, an ethoxyphenyl radical, a nitrophenyl radical and a Z-benzo- References cltedm the file of this Patent thiazolyl radical and R1 represents a member selected UNITED STATES PATENTS from the group consisting of a methyl group, a carboxyl group, a carbomethoxy group, a carboethoxy group, an 2 g g 'g'ggg is 22 group, a y y group and a trlfluoromethyl 2,218299 Schmid Oct. 1940 10. A complex nickel compound of the azo compound 2441612 Argyle et a1 May 1948 having the formula:

S\, CEIOzS v V CN=N-C-CH5 40 

1. AS A COMPOSITION OF MATTER, THE AZO COMPOUNDS SELECTED FROM THE GROUP CONSISTING OF MONOAZO COMPOUNDS AND THEIR METAL COMPLEXES CONTAINING A METAL SELECTED FROM THE GROUP CONSISTING OF CHROMIUM, COBALT, COPPER, IRON, MANGANESE, NICKEL AND VANADIUM, SAID MONOAZO COMPOUNDS HAVING THE FORMULA: 